带Key，Value实现的Combobox

struct itemEx
        {
            public object Value;
            public string Text;
            public itemEx(object value, string text)
            {
                this.Value = value;
                this.Text = text;
            }
            //重点是override ToString 
            public override string ToString()
            { return Text; }
        }

ComboBoxItemCollection coll = comboBoxEdit1.Properties.Items;
            coll.BeginUpdate();
            try
            {
                coll.Add(new itemEx("Sven", "Petersen"));
                coll.Add(new itemEx("Cheryl", "Saylor"));
                coll.Add(new itemEx("Dirk", "Luchte"));
            }
            finally
            {
                coll.EndUpdate();
                comboBoxEdit1.SelectedIndex = -1;
            }

private void comboBoxEdit1_SelectedIndexChanged(object sender, EventArgs e)
        {
            itemEx item = new itemEx();
            item = (itemEx)(this.comboBoxEdit1.SelectedItem);
            string strValue = item.Value.ToString().Trim();
        }